Revival Potion (5e Equipment)
From D&D Wiki
Potion, legendary (requires attunement)
This potion's bright solid orange color belays a mysterious power. Somehow, when a creature with this potion on them dies while they are attuned to it, this potion immediately shatters in a small but rather loud and messy explosion, reviving the holder if they were dead for less than a minute and healing them for 1d8 (per 5 character levels, up to 5d8 at level 20) +4 hit points. The potion will not go off if the character has been dead for more than a minute when the potion is given to them or if the potion is in an area where spells cannot be cast. A counterspell will also nullify the potion's effects if cast as a reaction to the potion exploding, ruining the potion in the process. The item doesn't require attunement if it is given to the dead person instead of being held by them, but requires an action to administer this way, and only works if given to them by the creature that is attuned to it.